Cold cathode discharge apparatus with memory functions

ABSTRACT

In a cold cathode ray discharge apparatus of the class comprising a first electrode acting as an anode, a plurality of second electrodes acting as cathodes, and an envelope containing the first and second electrodes and filled with a luminous inert gas, at least a portion of the envelope being transparent, there are provided insulator spacer means disposed between the first and second electrodes, the spacer means being provided with a plurality of perforations which form discrete discharge cells, a plurality of starting cathode electrodes disposed between the first and second electrodes, a plurality of starting anode electrodes disposed between the first electrode and the starting cathode electrodes and a plurality of resistors respectively connected to the second electrodes. Each ones of the second electrodes, the starting cathode electrodes, the starting anode electrodes cooperate with the first electrode and the spacer means to constitute a display unit. Responsive to a pattern signal an electric discharge is established between the starting anode and the starting cathode and then the discharge is transferred to between the first and second electrode thereby the display apparatus manifests a memory function.

United States Patent [191 Sasaki et a1.

[ Nov. 27, 1973 COLD CATHODE DISCHARGE APPARATUS WITH MEMORY FUNCTIONS [75] Inventors: Rentaro Sasaki; Akinori Watanabe,

both of Takasaki; Tatsuo Ogasawara, Tokyo; Satoshi Watanabe, Gyoda, all of Japan [73] Assignees: Oki Electric Industry Company Ltd.; Okaya Electric Industry Company, Tokyo, Japan [22] Filed: Sept. 29, 1972 21 Appl.No.:293,573

[30] Foreign Application Priority Data Sept. 30, 1971 Japan 46/76701 [52] US. Cl 313/217, 313/220, 315/169 R [51] Int. Cl. I-I0lj 61/06 [58] Field of Search 313/217, 220

[56] References Cited UNITED STATES PATENTS 3,626,245 12/1971 Rosenberg et al 313/220 Primary Examiner-Roy Lake Assistant ExaminerDarwin R. Hostetter Att0rneyC. Yardley Chittick et a1.

81111111111 amour [57] ABSTRACT In a cold cathode ray discharge apparatus of the class comprising a first electrode acting as an anode, a plurality of second electrodes acting as cathodes, and an envelope containing the first and second electrodes and filled with a luminous inert gas, at least a portion of the envelope being transparent, there are provided insulator spacer means disposed between the first and second electrodes, the spacer means being provided with a plurality of perforations which form discrete discharge cells, a plurality of starting cathode electrodes disposed between the first and second electrodes, a plurality of starting anode electrodes disposed between the first electrode and the starting cathode electrodes and a plurality of resistors respectively connected to the second electrodes. Each ones of the second electrodes, the starting cathode electrodes, the starting anode electrodes cooperate with the first electrode and the spacer means to constitute a display unit. Responsive to a pattern signal an electric discharge is established between the starting anode and the starting cathode and then the discharge is transferred to between the first and second electrode thereby the display apparatus manifests a memory function.

8 Claims, 5 Drawing Figures PATENTED NOV 2 71875 SHEET 3 BF 3 S E E N Q a Q a a a a COLD CATHODE DISCHARGE APPARATUS MEMORY FUNCTIONS BACKGROUND OF THE INVENTION This invention relates to a cold cathode discharge display apparatus with memory function.

The conventional cold cathode discharge display ap-' paratus comprises a pair of electrodes contained in an envelope filled with a luminous inert gas such as neon or argon gas and an information signal is applied across the electrodes to display a desired pattern.

In the commercial cold cathode discharge display apparatus sold under the trade marks of Clfin and Planitron a plurality of display units, each consisting of a plurality of segment electrodes and a counter electrode disposed to oppose the segment electrodes with a predetermined spacing therebetween, are disposed side by side in the same envelope. Such a display device is used to display patterns of a plurality of digits by selectively operating the display units on the time division basis at such a high speed that does not cause flickering.

However, because such a display device lacksmemory function it is necessary to provide an independent memory device thereby increasing the cost of manufacturing'and complicating the construction of the display device.

Further, it is necessary to increase the frequency of the time division signal when the number of digits or orders of the magnitude is increased.

SUMMARY OF THE INVENTION According it is an object of this invention to provide a new and improved cold cathode discharge display apparatus with a memory function so that the display apparatus can display continuously a' desired pattern without using any expensive external memory device.

Another object of this invention is to provide an improved cold cathode discharge memory apparatus of compact construction and capable manifesting a-memory function.

Yet another object of this invention is to provide an improved cold cathode discharge display apparatus capable of manifesting a memory function and including a plurality of display units thus continuously displaying patterns of multiple digits.

According to this invention, there is provided a cold cathode discharge display apparatus of the class comprising a first electrode, a pluraltiy of second electrodes confronting the first electrode, and an envelope containing the first and second electrodes and filledwith a luminous inert gas, at least a portion of the envelope being transparent, characterized in that there are provided insulator spacer means disposed between the first and second electrodes, the spacer means being provided with a plurality of perforations which form discrete discharge cells, a plurality of starting cathode electrodes disposed between the first and second electrodes, a plurality of starting anode electrodes disposed between the first electrode and the starting cathode electrodes, and a plurality of resistors respectively connected to the second electrodes; and that each ones of the second electrodes, the starting anode electrodes and starting cathode electrodes cooperate with the first electrode and the spacer means to constitute a display unit.

BRIEF DESCRIPTION OF THE DRAWINGS" Further objects and advantages of the invention will be more fully understood from the following detailed description taken in conjunction with the accompanying drawings in which:

FIG. 1 is an explodedperspective view of various component elements of one example of a cold cathode discharge display apparatus embodying the invention;

FIG. 2 is a plan view showing the starting electrodes shown in FIG. 1;

FIG. 3 shows a section, in an enlarged scale, of a portion of the cathode electrode employed in the display apparatus shown in FIG. 1;

FIG. 4 shows a cross-sectional view of an assembly of various component elements shown in FIG. 1; and

FIG. 5 shows an equivalent circuit of the embodiment shown in FIGS. 1 and 4.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the accompanying drawings, a preferred embodiment of the cold cathode discharge display apparatus 1 shown in FIG. 1 comprises an upper substrate 2 and a lower substrate 3 which are made of sheets of transparent material such as glass and form a portion of the envelope as will be described later. Between the upper and lower substrates 2' and'3 are disposed a plurality of anode electrodes 5a and 5d, each formed with a plurality of perforations 4 arranged'in a matrix and forming a portion of a display unit, a plurality of starting anode electrodes 6a through 6d having substantially the same construction as the anode electrodes, a starting cathode substrate 7 formed with a plurality of perforations 12 that aligne with the perforations 4 of the anode electrodes 5a through 511' and a cathode substrate 8 provided with similar perforations. First, second and third spacers 9, l0 and 11 each provided with a plurality of perforations which are arranged in a matrix and are aligned with those of the anode and cathode electrodes are interposed respectively between anode electrodes 5a through 5d and starting anodes 6a through 6d, between starting anodes 6a through 6d and starting cathode substrate 7, and between the starting cathode substrate 7 and'the cathode substrate 8. The perforations of the starting cathode substrate 7 are lined with through hole platings 12 which are used as the starting cathode electrodes. Corresponding starting cathode electrodes of respective display units including groups of perforations are connected to terminals 13, as shown in FIG. 2, which are formed on the upper and lower surfaces of the'opposite ends of the substrate 7 as by printing.

As shown in FIG. 3, the cathode substrate 8 comprises a sheet of insulator provided with a plurality of perforations, and solid state resistors 14' formed by compressing a powder of glass or ceramic are disposed in the perforations through the substrate 8, these perforations being also arranged in a matrix. On the surfaces of the resistors 14 facing the anode electrodes 5a through 5d are provided cathode electrodes 15' which are formed by plating nickel films, for example. The opposite surfaces of the resistors 14 are electrically connected to a thin sheet 16 having substantially the same coefficient of thermal expansion as the lower substrate 3 of glass or ceramic, the thin sheet 16 acting as a common lead wire for respective resistors 14.

Above described substrates, electrodes, and spacers are superposed one upon the other as shown in FIG. 4 to form a lamination and the periphery of the lamination is hermetically sealed with first glass or the like. After evacuating the interior of the envelope thus formed, a luminous inert gas such as neon or argon gas is filled in the envelope thereby completing a cold cathode discharge display apparatus of this invention.

FIG. 5 shows an equivalent circuit of this display apparatus. To operate this display apparatus a matrix driving member 20 is provided and the output thereof is applied to the terminals 13a through l3n of the starting cathode electrodes through protective resistors 21a through 2111 of high resistance values. The cold cathode discharge display apparatus comprises four display units 22a to 22d. The spacings between anode electrodes 5a through 5d, cathode electrode 15, starting anode electrodes 6a through 6d and starting cathode electrodes 12 are selected to satisfy the following conditions. A. The breakdown or discharge initiating voltage between anode electrodes 5a through 50 and the cathode electrode 15 is higher than the breakdown voltage between the starting anodes 6a through 6d and the voltage for sustaining the discharge between a starting anode electrode and a starting cathode electrode is lower than the voltage impressed upon these electrode. B. The breakdown voltage between a starting anode and a starting cathode is higher than the discharge sustaining voltage between these electrodes.

Typical values of these voltages are as follows: Breakdown voltage between an anode electrode and a cathode electode 200V,

Discharge sustaining voltage between an anode electrode and a cathode electrode 130V,

Breakdown voltage between a starting anode and a starting cathode 180V, and

Discharge sustaining voltage between a starting electrode and a starting cathode 180V.

The cathode electrodes 15 of the display apparatus are connected to a common source of 5OV respectively through resistors 14.

In operation, a pulse signal of-HSOV is applied upon starting anode 6a of a display unit to be operated, the first display unit 22a for example. At the same time, an input signal is applied to the matrix driving unit 20. Responsive to this input signal the matrix driving unit selects one of the terminals 130 through 13m of the starting cathode electrodes corresponding to the pattern information contained in the input signal for supplying a negative pulse signal to a selected terminal, 130 for example. As a result, the potential difference between the starting anode 6a and the starting cathode 12 of the first display unit 22a is increased to 200V which is higher than the predetermined breakdown voltage (180V) between these electrodes thus initiating a discharge therebetween.

When a voltage of 150V which is somewhat higher than the discharge sustaining voltage 130V between a starting anode and a starting cathode is impressed upon anode electrode 5 a of the first display unit 220 a discharge will be created between anode electrode 5a and cathode electrode 15 corresponding to the selected starting electrode 12 and such a discharge can be seen through the transparent upper substrate 2. Since the signal impress across the starting anode and the selected starting cathode 12 is a pulse, the input signal disappears after a definite time but since the potential difference between anode electrode 5a and cathode electrode 15 equals V which is higher than the discharge sustaining voltage (l3OV) between the anode and cathode electrode, the discharge will be sustained between anode electode 5a and cathode electrode 15 of the first display unit 220 irrespective of the input signal impressed upon the starting electrode 6a and starting cathode 15 thereby manifesting memory function.

Where it is desired to display a pattern on the second display unit 22b, the pulse signal of 200V is impressed across the starting anode 6b of the second display unit 22b and a starting electrode 12 selected in accordance with a desired pattern to be displayed. Then a discharge will be resulted between the starting anode 6b and the starting cathode of the second display unit 2217. Under these condition, when a voltage of 150V is impressed between anode electrode 5b and cathode electrode 15 of the second display unit 22b a discharge is established between these electrodes which is sustained irrespective of the condition of the input signal.

When the second display unit 22b is actuated in this manner, the input signal is applied also to the starting cathode of the first display unit 22a but no discharge will be created between the starting anode 6a and the starting cathode 15 of the first display unit 220 because no pulse signal is applied across the starting anode 6a of the first display unit 22a.

In this manner, in the cold cathode discharge display apparatus described above, the pulse signal supplied to a starting cathode electrode 12 functions as a pattern selection signal, the signal applied to a starting anode electrode functions as a pattern display position designating signal and the voltage impressed upon anode electrodes 5a through 5d acts as a memory signalv For this reason, it is possible to erase or correct the pattern displayed on any one of display units 220 through 220' by removing the voltage applied to one of the anode electrodes 5a through 5d without providing external memory device. Since aligned perforations of spacers 9, l0 and 11 form discrete discharge cells between the anode electrodes 5a and respective cathode electrodes 15, the discharge between selected starting anode and starting cathode would not affect another electrodes.

Although in this embodiment, the starting cathodes are formed by printing, it should be understood that these electrodes may be formed by other processes, for example multi-layer printing.

As above described this invention provides a novel cold cathode discharge display apparatus having by itself a memory function so that it is not necessary to provide a external memory device thus greatly simplifying the construction and greatly reducing the cost of manufacturing. When the novel display apparatus is constructed to have a plurality of display units it is possible to display patterns of multiple digits without driving the display apparatus on the time division basis by providing a complicated driving circuit as has been the practice in the prior art cold cathode discharge display apparatus.

What is claimed is:

1. A cold cathode discharge display apparatus comprising a first electrode, a plurality of second electrodes spaced from said first electrode, insulative spacer means disposed between said first and second electrodes, said spacer means being provided with a plurality of perforations which form discrete discharge cells, a plurality of starting cathode electrodes disposed between said first electrode and said second electrodes, a plurality of staring anode electrodes disposed between said first electrode and said starting cathode electrodes, a plurality of resistors respectively connected to said second electrodes, each ones of said second electrodes, said starting cathode electrodes and said starting anode electrodes cooperating with said first electrode and said spacer means to constitute a display unit, and an envelope containing all of said component elements and filled with a luminous inert gas, at least a portion of said envelope being transparent.

2. The display apparatus according to claim 1 wherein said first electrode, said starting cathode electrode, said starting anode electrodes and said second electrodes are provided with a plurality of perforations aligned with the perforations of said spacer means, all of said perforations being arranged in a plurality of matrixes, one for each display unit.

3. The display apparatus according to claim 1 wherein said spacer means comprises a plurality of perforated insulator sheets which are respectively interposed between said first electrode and said starting cathode electrode, between said starting cathode electrode and said starting anode electrodes, and between said starting anode electrodes and said second electrodes, and wherein the perforations of said plurality of insulator sheets are in alignment with those of said starting cathode electrode, said starting anode electrodes and said second electrodes.

4. The display apparatus according to claim 1 wherein said second electrodes comprises an insulator sheet provided with a plurality of perforations which are grouped into a plurality of matrixes. a plurality of resistors contained in respective perforations, and thin metal layers respectively applied on one ends of said resistors.

5. The display apparatus according to claim 1 wherein said starting cathode electrodes comprise an insulator sheet provided with a plurality of perforations which are grouped into a plurality of matrixes, and a plurality of metal films applied on the inner walls of said perforations.

6. The display apparatus according to claim 1 wherein said first electrode comprises a plurality of rectangular anode electrodes, said starting anode electrodes have a configuration identical to that of said anode electrodes, and each anode electrode and each starting anode electrode are provided with aligned perforations which are arranged in matrixes.

7. The display apparatus according to claim 1 including means for applying an information signal of a pattern to be displayed on said starting cathode electrodes, means for applying a predetermined potential upon said first electrode and means for applying a potential higher than said pre-determined potential on said starting cathode electrodes.

8. The display apparatus according to claim 1 wherein said component elements are superposed one upon the other between a pair of transparent substrate to form a lamination, and the periphery of said lamination is hermetically sealed to form said envelope. 

1. A cold cathode discharge display apparatus comprising a first electrode, a plurality of second electrodes spaced from said first electrode, insulative spacer means disposed between said first and second electrodes, said spacer means being provided with a plurality of perforations which form discrete discharge cells, a plurality of starting cathode electrodes disposed between said first electrode and said second electrodes, a plurality of staring anode electrodes disposed between said first electrode and said starting cathode electrodes, a plurality of resistors respectively connected to said second electrodes, each ones of said second electrodes, said starting cathode electrodes and said starting anode electrodes cooperating With said first electrode and said spacer means to constitute a display unit, and an envelope containing all of said component elements and filled with a luminous inert gas, at least a portion of said envelope being transparent.
 2. The display apparatus according to claim 1 wherein said first electrode, said starting cathode electrode, said starting anode electrodes and said second electrodes are provided with a plurality of perforations aligned with the perforations of said spacer means, all of said perforations being arranged in a plurality of matrixes, one for each display unit.
 3. The display apparatus according to claim 1 wherein said spacer means comprises a plurality of perforated insulator sheets which are respectively interposed between said first electrode and said starting cathode electrode, between said starting cathode electrode and said starting anode electrodes, and between said starting anode electrodes and said second electrodes, and wherein the perforations of said plurality of insulator sheets are in alignment with those of said starting cathode electrode, said starting anode electrodes and said second electrodes.
 4. The display apparatus according to claim 1 wherein said second electrodes comprises an insulator sheet provided with a plurality of perforations which are grouped into a plurality of matrixes, a plurality of resistors contained in respective perforations, and thin metal layers respectively applied on one ends of said resistors.
 5. The display apparatus according to claim 1 wherein said starting cathode electrodes comprise an insulator sheet provided with a plurality of perforations which are grouped into a plurality of matrixes, and a plurality of metal films applied on the inner walls of said perforations.
 6. The display apparatus according to claim 1 wherein said first electrode comprises a plurality of rectangular anode electrodes, said starting anode electrodes have a configuration identical to that of said anode electrodes, and each anode electrode and each starting anode electrode are provided with aligned perforations which are arranged in matrixes.
 7. The display apparatus according to claim 1 including means for applying an information signal of a pattern to be displayed on said starting cathode electrodes, means for applying a predetermined potential upon said first electrode and means for applying a potential higher than said pre-determined potential on said starting cathode electrodes.
 8. The display apparatus according to claim 1 wherein said component elements are superposed one upon the other between a pair of transparent substrate to form a lamination, and the periphery of said lamination is hermetically sealed to form said envelope. 